There is a hardware firewall ( an european product : Netasq , the "head")in the school network. It's a physical router. It's make real-time intrusion prevention, network and application firewall, advanced content filtering, , antispam, antispyware, URL filtering, IPSEC and SSL VPN . So, as you said, there is no need to deploy on each PC. But, in France, The Politic in the Education and Internet is too prevent every sort of mistakes about Internet ( log to site of Violence, Racism, Terrorism, .... ) or local intrusions. So, I have to install on computers ( in + of the hardware solution ) Firewall, antispyware and tools ( like ccleaner ). With over than 80 PC's in the network, I work on a silent install of these applications. But I don't know if the deployement of the applications is possible ( in silent install ) with multiple users ( administrator, teachers, studients ) and without I have to configure the firewall, the antispyware for each user. I hope you understand. Kenavo